1. Field of the Invention
The present invention relates to an illumination system which illuminates an object to be illuminated.
2. Description of the Related Art
For example, in Jpn. Pat. Appln. KOKAI Publication No. 2008-26698, there is disclosed a light emitting device which is a light source device having a constitution capable of detecting disconnection with high accuracy. This light source device includes a light source having a semiconductor light emitting element to emit light (for example, excitation light), a lens which condenses the light emitted from the semiconductor light emitting element, a connector on which the light is condensed by the lens, a light guiding member connected to the connector, and an optical part disposed at a tip of the light guiding member. The light guiding member guides the light condensed on the connector. An example of the light guiding member is an optical fiber. The light is guided to the optical part by the light guiding member.
Moreover, the above light source device further includes a light branching member, which is interposed between the lens and the connector, to branch the reflected light returned from the optical part, and a light receiving element which receives the reflected light branched by the light branching member. The light receiving element is also a detecting section which detects the reflected light to detect the presence/absence of a failure of the light source device, for example, the disconnection of the light guiding member.
Jpn. Pat. Appln. KOKAI Publication No. 2008-26698 described above uses a constitution which detects reflected light branched by a light branching member to detect a failure such as disconnection of a light guiding member. However, detection items to be detected by such reflected light are limited, and when the measurement items are increased for the purpose of precisely detecting the failure, it is necessary to mount detectors on a light source device, which brings about an increase in the size of the device.